Religion News Service reports that a new book about Christian identity is inadvertently tapping into the U.S.’s racial history:

For evangelical author John MacArthur, the best way to explain a Christian’s relationship to Jesus is what appears to be a simple metaphor—one often used by the Apostle Paul himself.

“To be a Christian is to be a slave of Christ,” writes MacArthur, the pastor of a nondenominational church in Sun Valley, Calif.

His new book, “Slave: The Hidden Truth About Your Identity in Christ,” explores the varied practices of Bible translators regarding the controversial term. It’s also drawing mixed reactions among African-American Christians whose ancestors were slaves in 19th-century America.

MacArthur views the issue in almost conspiratorial terms: While biblical texts use the word “slave” to describe actual slave-master relationships in biblical times, English translators often opt for the word “servant” when describing a believer’s relationship to God.

Read the full feature here.